1. Field of the Invention
The present invention is generally in the field of semiconductors. More particularly, the invention is in the field of fuse structures used in semiconductor dice.
2. Background Art
One-time programmable cell structures, which can be programmed only once, can be generally utilized in any integrated circuit (IC) chip for storing information that is to be retained when the cells are no longer supplied with power. For example, one-time programmable cell structures can be utilized for storing information related to device identification, characteristics, and fabrication processes. A one-time programmable cell structure is typically programmed in a programming operation that irreversibly alters a portion of the cell structure.
Conventional one-time programmable cell structures have utilized mechanisms such as gate oxide breakdown and hot carrier injection to provide programmability. However, gate oxide breakdown and hot carrier injection can require a high voltage, which, in turn, can require a charge pump and associated circuitry. The charge pump and the associated circuitry for providing the necessary high voltage can undesirably increase power consumption, complexity, and cost. Silicide and interconnect metal fuses have also been utilized in conventional one-time programmable cell structures to provide programmability. However, silicide and interconnect metal fuses can require an undesirably high programming current.